CCSD3ZF0000100000001NJPL3IF0PDSX00000001
/* FILE: J0CD_IFL2_EUV_EUVON.XLBL */
/* VERSION 1.4: 18-MAY-1999 MOSSER */
PDS_VERSION_ID = PDS3
RECORD_TYPE = FIXED_LENGTH
RECORD_BYTES = 4528 /*=1132*4 */
FILE_RECORDS = 3
PRODUCT_ID = "J0CD_IFL2_EUV_EUVON.DAT"
PRODUCT_NAME = "J0IFL2_EUVON EDR DATA"
DATA_SET_ID = "GO-
OBSERVATION_ID = "J0IFL2_EUVON"
SPACECRAFT_NAME = "GALILEO ORBITER"
INSTRUMENT_NAME = "EXTREME UV SPECTROMETER"
MISSION_PHASE_NAME = "JUPITER ORBIT OPERATIONS"
TARGET_NAME = "STAR"
PRODUCT_CREATION_TIME = "7-MAR-1997"
START_TIME = 1996-145T16:11:47.414Z
STOP_TIME = 1996-150T15:45:37.412Z
SPACECRAFT_CLOCK_START_COUNT = "3449764:00:0"
SPACECRAFT_CLOCK_STOP_COUNT = "3456859:00:0"
^SPECTRUM = "J0CD_IFL2_EUV_EUVON.DAT"
DESCRIPTION = "
This file was produced by the Galileo UVS/EUV team at the Laboratory
for Atmospheric and Space Physics (LASP) at the University of Colorado
at Boulder. Refer to the Galileo UVS/EUV instrument paper 'Galileo
Ultraviolet Spectrometer Experiment', Vol 60, Space Science Reviews,
pages 503-530, by C.W. Hord et al, for hardware and calibration
information and to the EUV Instrument template for a description
of the Phase 2 (P2) data summation in the EUV internal buffer.
The data contained in the file is IEEE XDR interchange format. MAY, 1999
The EUV data in this file were obtained using the EUV P2 RTS mode.
Check the commanded configuration in the flight sequence for the most
accurate understanding of these data. Calibration to physical units
has not been made; the data are in units of 'raw counts per time'.
The commanded instrument summation period, number of sky sectors and
number of detector pixels summed are given in the command. The EUV
integration time and sampling of the grating positions by use of a
'Fixed Pattern Noise Table' (FPNT) are described in the instrument
template. Some command information is given in the engineering data
embedded in the data portion of the record.
The analysis of these raw data has not been published at this time.
The data in this file was obtained using the GENERAL FPN table.
A diagram of the file and record structure is shown below:
|-----+---------------|
1 |time | S | EUV RTS SUMMATION BUFFER
|-----+---------------| .
2 |time | S | .
|-----+---------------| .
3 |time | S | .
|-----+---------------| .
. .
. repeats .
. .
|-----+---------------| .
ij |time | S | EUV RTS SUMMATION BUFFER
|-----+---------------|
|40 4-| /S= \
|byte | /1092 \
|time | /4-byte \
|tags | /spectral \
|& hdr| / values \
Records 1 to ij are data records. Each record begins with a 160-byte
header containing 40 4-byte integer numbers. The header values are
described below, the exact definition of the time values is further
described in the Galileo document 625-610. The time tags given in
the data records refer to the time of the first integration period
included in the packet summation period; the STOP time refers to the
Rim time of the FLUSH command, which represents one Rim greater than
the true summation period; these are derived from the EUV downlinked
packets. The LABEL START and STOP time values refer to the FLUSH
times as well.
The data start at byte 161, following the header information. Each
record contains one readout (termed FLUSH in the sequences) of the
EUV Internal Buffer (EIB). The EIB contains the EUV sky-sector/pixel
matrix summed over the Summation Period (an even number of Rims.)
At the time of a FLUSH command, the CDS computer moves the buffer from
the EUV microprocessor buffer to the downlink processing buffer, taking
one full RIM to move the contents and send the EUV flag to zero it.
The duration of the FLUSH periods is given by the data label start and
stop times, and is generally one-half hour, one hour or 24 hours - minus
the one RIM to transfer the data - but may be a subset of these. Each
data record in the file can contain data from a different summation
duration.
Simply, the EUV samples areas of the sky, on each revolution, based on
the command and the instrument integration time. The fixed EIB size is
divided into sky-sectors by pixels. To utilize the space efficiently,
the detector pixels are also summed over useful wavelengths; a table
defining the pixel sums, FPNT, is loaded to the microprocessor each
time the EUV is powered-On for the orbit data taking and is therefore
available in the command sequence. For the P2 mission phase, there
are three commonly used tables: TORUS, AURORA, and GENERAL.
An EUV matrix has 24x45 data values followed by 24 housekeeping values.
Some engineering operation (Temperature) values are available in the
AACS records but are not included in the data records.
The data matrix is arranged internally and read out so that the order
of the matrix is: 1st value=(sector 1, lowest pixel sum), 2nd value=
(sector 1, next pixel sum) so that all the pixels in one sector are
read out before the next sector's pixels are placed into the downlink
stream. They are, in order of presentation:
1 - fiducial, VALUE=7E (hex)
2 - fiducial, VALUE=7E (hex)
3 - TRANSITION SECTOR PAIR, MOD 64 - how many pixel pairs to ignore
before starting integration
4 - COMMANDED PIXEL PAIR SUMS, - times 2, read from the FPNT
5 - echo of COMMANDED STARTING ANGLE - the value has unit size
of (360.0 degrees/256.)
6 - echo of COMMANDED HIGH VOLTAGE LEVEL (always should be 3)
7 - echo of COMMANDED SCANS/SECTOR
8 - echo of COMMANDED SECTORS - may be changed by micro software
9 - NEXT TO LEAST SIGNIFICANT BYTE OF RIM COUNTER - prior to the
beginning of the last integration
10 - LEAST SIGNIFICANT BYTE OF RIM COUNTER
11 - MOD91 OF RIM COUNTER ( = minor frame)
12 - MOD10 OF RIM COUNTER ( = RTI, Real Time Interrupt count)
13 - NEXT TO LEAST SIGNIFICANT BYTE OF DELTA THETA - Delta Theta
is in units of degrees of sky in 66 2/3 msec (one RTI); the
increment is 360/16,777,216 degrees.)
14 - LEAST SIGNIFICANT BYTE OF DELTA THETA
15 - MOST SIGNIFICANT BYTE OF THETA - Theta increment is
360/65,536 degrees.
16 - LEAST SIGNIFICANT BYTE OF THETA
17 - SOFTWARE VERSION NUMBER - P2 starts at 40
18 - MOST SIGNIFICANT BYTE OF 16-BIT INTEGRATION COUNTER
19 - LEAST SIGNIFICANT BYTE OF INTEGRATION COUNTER - this is the
true number of revolutions (spins) EUV actually integrated
20 - EXACT CURRENT RTI - the actual value at time this is sampled;
Values 15-19 pertain to the exact time
21 - TRANSITION SECTOR PAIR, MOD 200
22 - REAL TIME MINOR FRAME COUNTER - actual mf at this sample time
23 - SYNC COUNTER - the number of times the s/w has had to wait to
sync up with the s/c time; expected value = 1
24 - spare
up to 1080 values 24 values
|-----------------------------------------|-----------|
| one EUV summation matrix |engineering|
All values in the EIB are summed, excluding the fiducials and
engineering values. The 2-byte EIB rolls over and begins counting
again from value zero.
TORUS1:[GLL_RAW.INFO]EUV_PHASE2_RTS_HDR.DOC
June 10, 1996 - Jeremy Gebben
In phase 2 Real Time operations, the EUV instrument stores
data in a 24 sector by 45 pixel matrix. Every few RIMs, this matrix
and 24 bytes of housekeeping data are read out and cleared.
These data sets are stored in IDL associate files formated as
lonar(1132).
HEADER:
Earth Receipt Time
0 = Year (last 2 digits eg. 96)
1 = day of year
2 = hours
3 = minutes
4 = seconds
5 = milliseconds
Spacecraft Event time for start of integration:
6 = Year (last 2 digits eg. 96)
7 = day of year
8 = hours
9 = minutes
10 = seconds
11 = milliseconds
SCLK time for start of integration:
12 = start RIM (all realtime data starts on mf 0)
Spacecraft Event time for end of integration:
13 = Year (last 2 digits eg. 96)
14 = day of year
15 = hours
16 = minutes
17 = seconds
18 = milliseconds
SCLK time for end of integration:
19 = end RIM (all realtime data ends on mf 0)
20 = # of packets that went into this array(max = 8)
Data presence Indicators:
21-28 = dpi flags,1 for each packet
Each is a 4 byte field:
Top byte:
00 = no data missing
FF = entire packet missing
01 = data missing at end of packet
02 = data missing in middle of packet
03 = data missing at end of packet
Lower 3 bytes are only used if the top byte is 01,02, or 03
In these cases, the three lower bytes are used to report
the position of the gap:
second byte: # of data words(2 bytes)
at start(0 if gap is at start)
third byte : # of data words missing
bottom byte: # of data words at end of packet
(0 if gap is at end)
29 = packet sequence # of the first packet in this set
30,31 = spare (set to -1)
32 = software version number
33-39 = spare (set to -1)
DATA:
40-1119 = data matrix(24*45) all pixels from sector 1,
then all pixels from sector 2 ...
1120-1131 = housekeeping values(2 bytes each)
........................................................"
OBJECT = SPECTRUM
NAME = "ONE EUV RTS SUMMATION BUFFER"
INTERCHANGE_FORMAT = BINARY
ROWS = 3
COLUMNS = 41
ROW_BYTES = 4528
^STRUCTURE = "EUV_P2_RTS.FMT"
DESCRIPTION = "
The summation data table consists of 40 4-byte integers of time tags
(RIM, yr, doy, hr, min, sec, etc), data quality flags and spares, and
1092 spectral values for one summed spectral pair. The
record structure is the same as the table. "
END_OBJECT = SPECTRUM
END